R help - Oct 2009 - Problem Removing Border Lines in Maps Package

I'm working with the nationwide county maps data, and trying to remove the
internal county boundary lines.  The only map() function parameter that I've
found that gets me anywhere close to my desired result leaves small white
segments on parts of the map.  I believe this is due to the low resolution,
because when I look at individual states, the lty parameter solves the
problem.  Does anyone have any idea how I might draw a United States county
map without these white borders making the map look sloppy?

library(maps)

#county map of new jersey, with invisible county borders -- correct example
map("county","new jersey", fill=TRUE , col=palette() ,
lty=0)

#county map of the united states, with white county borders still visible
some places
map("county", fill=TRUE , col=palette() , lty=0)

Thanks

	[[alternative HTML version deleted]]

If you don't want the county boundaries, then don't use the county map. 
There is the state database that does not have county information.

If you want the counties different colors, but no dividing lines, then you may
want to try the maptools and sp packages (shapefiles for the states/counties is
available on the web) which use a different algorithm for storing and drawing
the maps and will let you draw the outlines in the same color as the fill.

-- 
Gregory (Greg) L. Snow Ph.D.
Statistical Data Center
Intermountain Healthcare
greg.snow at imail.org
801.408.8111

> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-
> project.org] On Behalf Of Anthony Damico
> Sent: Saturday, October 24, 2009 12:40 PM
> To: r-help at r-project.org
> Subject: [R] Problem Removing Border Lines in Maps Package
> 
> I'm working with the nationwide county maps data, and trying to remove
> the
> internal county boundary lines.  The only map() function parameter that
> I've
> found that gets me anywhere close to my desired result leaves small
> white
> segments on parts of the map.  I believe this is due to the low
> resolution,
> because when I look at individual states, the lty parameter solves the
> problem.  Does anyone have any idea how I might draw a United States
> county
> map without these white borders making the map look sloppy?
> 
> library(maps)
> 
> #county map of new jersey, with invisible county borders -- correct
> example
> map("county","new jersey", fill=TRUE , col=palette() ,
lty=0)
> 
> #county map of the united states, with white county borders still
> visible
> some places
> map("county", fill=TRUE , col=palette() , lty=0)
> 
> Thanks
> 
> 	[[alternative HTML version deleted]]
> 
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-
> guide.html
> and provide commented, minimal, self-contained, reproducible code.

Have a look at:
map("county", fill=TRUE , col=palette() , resolution=0, lty=0)

HTH,
Ray Brownrigg

Anthony Damico wrote:
> I'm working with the nationwide county maps data, and trying to remove
the
> internal county boundary lines.  The only map() function parameter that
I've
> found that gets me anywhere close to my desired result leaves small white
> segments on parts of the map.  I believe this is due to the low resolution,
> because when I look at individual states, the lty parameter solves the
> problem.  Does anyone have any idea how I might draw a United States county
> map without these white borders making the map look sloppy?
> 
> library(maps)
> 
> #county map of new jersey, with invisible county borders -- correct example
> map("county","new jersey", fill=TRUE , col=palette() ,
lty=0)
> 
> #county map of the united states, with white county borders still visible
> some places
> map("county", fill=TRUE , col=palette() , lty=0)
> 
> Thanks